This invention relates to devices for the testing of wiring for continuity, open, short circuit or mis-wire.
The type of wiring towards which this invention is specifically directed, is wiring harnesses such as are made up for most electrical equipments. Printed Wiring Board assemblies (PWBA's) and Card Cages may also be tested by the invention.
Wiring analysis and testing devices have been known and available for a good many years. These devices range from those analyzers designed for cable testing such as U.S. Pat. No. 2,810,881, Automatic Cable Tester by W. E. Daily, to those designed for identifying matching wires, as described by U.S. Pat. No. 4,114,091, to J. L. Howard. Other devices, including U.S. Pat. No. 4,929,902 to W. A. Nelson, are specially directed to the test of coaxial cables and can not easily be adapted for wiring harnesses. In the typical factory, wiring harnesses are tested using very complex equipment. A single wiring harness under test may easily have more than fifty separate wires in a bundle. In order to handle this amount of wires, the presently available analyzer would need the same number of test circuits as wires under test. As a result, the analyzer is usually large and heavy, requiring that the harness be brought to it rather than moving the analyzer to the harness. The analyzer equipment is also expensive, in the order of tens of thousands of dollars because of its complexity.
There appear to be no wiring analyzers, whether patented and/or marketed, which are simple, light weight and inexpensive while being suitable for use in the test of multi-wire harnesses having large numbers of wires. It is thus an objective of the present invention to provide a wiring analyzer suitable for test of multi-wire harnesses, which is inexpensive, manually operated, portable and capable of being easily moved to various test locations.
Another object of the present invention is the provision of a wiring analyzer that is easy to operate and incorporates display indications of wiring faults.
Yet another object is the provision of a test circuit which may be used to test Printed Wiring Board assemblies and Card Cages for short circuits.
Other objects and advantages of the present invention will become apparent from a study of the following detailed description, the claims and the drawings illustrating the preferred embodiment.